The Effective Factors on SO2 Removal by Using Two Series Non-Thermal Plasma Reactors Combined with TiO2 and ZnO Photocatalysts

SO ₂ is one of the major air pollutants affecting both the environment and human health. Controlling its emissions has become a critical goal for many countries. Various technologies exist for SO ₂ removal, among which non-thermal plasma systems combined with photocatalysts stand out as particularly effective. This study evaluates the performance of a combined system utilizing non-thermal plasma and photocatalysts for SO ₂ removal, with data analyzed through SPSS and R software. In this method, SO ₂ was diluted with dry air and nano-photocatalysts of TiO ₂ and ZnO were used in IPC form to remove the pollutant. The study examined the effects of multiple variables – including concentration, flow rate, voltage, specific input energy, and residence time – on removal efficiency, as well as their interactions. ANOVA results showed that both systems were highly effective at removing SO ₂ , though the non-thermal plasma system paired with TiO ₂ photocatalyst performed slightly better. At a concentration of 500 ppm, SO ₂ removal efficiency reached 97.32% in the TiO ₂ -based system and 94.3% in the ZnO-based one. The best efficiency for both methods was achieved at a voltage of 15 kV and a flow rate of 3 Lit/Min. Results revealed this approach highly effective, efficient, and cost-effective for SO ₂ removal.